Alarm device

ABSTRACT

An alarm device having an extendible cord control element the outer end of which is attached to an object, such as a window or door, to place the cord in predetermined tension with the cord acting directly on a switch arm to effect an alarm signal upon a change in tension of the cord resulting from breaking or pulling thereof.

United States Patent 1191 Beiswenger et al. 1 June 3, 1975 54] ALARMDEVICE 2,780,689 2/1957 La Cavera 340/276 x [75] inventors: John L.Beiswenger, Pacific 52:2? gig 2 i Palisades; Leland Jorgensen, 3171311321/1973 Tonkow i c h lill...........::::l: 340/274 x v Chippewa Falls,both of Wis. [73] Assignee: National Presto Industries, Inc., EauFOREIGN PATENTS B APPLICATIONS Claire, Wis 1,068,127 5/1967 UnitedKingdom 200/153 H [22] Filed: 1972 Primary Examiner.l0hn W. Caldwell[21] App], No; 248,050 Assistant Examiner-Scott F. Partridge Attorney,Agent, or Firm.lohnson, Dienner, Emrich & Wagner [52] US. Cl. 340/274;ZOO/61.62; 340/276 [51] Int. Cl G08b 13/00; G08b 13/08 [58] Field ofSearch 340/274, 276, 283, 273, [57] ABSTRACT 340/420 232; 200/6139 Analarm device having an extendible cord control element the outer end ofwhich is attached to an object, [56] References cued such as a window ordoor, to place the cord in prede- UNITED STATE PATENTS termined tensionwith the cord acting directly on a 763,386 6/1904 Fitch 340/276 switcharm to effect an alarm signal upon a change in 793,775 7/1905 Esser340/276 tension of the cord resulting from breaking or pulling 1,238,5328/1917 Lemberg 340/283 UX thereof 1,452,500 4/1923 Galerman 340/2742,767,268 10/1956 Levine ZOO/61.39 11 Claims, 5 Drawing Figures v /6 l8=5555555e ji ,4, 1 55555555 I188 uazssssss n n u u u n u n u 1' [l2 7,0

M L 2% l2 1* M ALARM DEVICE BACKGROUND OF THE INVENTION The presentinvention relates generally to alarm devices, and more particularly to aburglar alarm device having novel switch means operative in response tothe change in tension of a control element to effect an alarm signal.

Burglar alarm devices are known which employ trip wire means attachableto a window or the like such that unauthorized opening or entry willeffect an alarm signal. For example, U.S. Pat. Nos. 118,199 to Cock andGuest, 1,238,532 to Lemberg, and 1,937,134 to Stout disclose burglaralarm mechanisms utilizing trip cord or chain means which are connectedto an object such that a change in tension of the cord as throughmovement of the object effects an alarm signal. The present inventionprovides an improved alarm device of this general type which includesnovel structural and functional advantages over the prior art devices.

SUMMARY OF THE INVENTION In accordance with a preferred embodiment ofthe present invention, an alarm device is provided having housing meanswhich encloses electrically operative alarm signal means and a source ofelectrical energy to selectively energize the signal means. The energysource is connected to the alarm signal means through a circuit whichincludes a control switch having a contact arm movable to contact eitherof a pair of spaced fixed contacts. The contact arm is supported forpivotal movement about the rotational axis of a reel which has a lengthof cord wrapped therearound. The cord directly engages the contact armand has magnetic attachment means on its outer end allowing it to be ledfrom the reel and attached to an object such as a window or door or thelike. The reel is manually adjustable from outside the housing to placethe cord under a predetermined tension and position the contact armintermediate the fixed contacts. When the cord is pulled or broken byunauthorized movement thereof, the contact arm is caused to contact oneof the fixed contacts and energize the alarm signal means. A key may beremovably inserted into the housing to open the circuit to the alarmsignal means during adjustment of the reel and contact arm. Thermostatmeans are preferably connected in circuit with the alarm signal means toestablish an alarm when the ambient temperature surrounding the housingreaches a danger level such as in the case of fire.

Accordingly, one of the primary objects of the present invention is toprovide an alarm device having novel means for establishing an alarmsignal upon unauthorized movement of a control element of the device.

Another object of the present invention is to provide an alarm devicewhich employs a novel contact switch arrangement responsive tounauthorized movement of a control cord having an outer end secured toan object such as a window or door or the like.

Another object of the present invention is to provide an alarm device asdescribed wherein the control cord is supported on a rotatable reel andacts directly on a contact arm movable in response to a change intension in the cord to contact one of a pair of fixed switch contactsand thereby energize alarm signal means.

A further object of the present invention is to provide an alarm devicewhich is relatively inexpensive to manufacture and highly efficient inoperation.

A feature of the present invention is a provision of a circuit disablingkey which may be removably inserted into the housing to disable thecircuit during adjustment of the control cord and movable contact arm.

Further objects and advantages of the present invention, together withthe organization and manner of operation thereof, will become apparentfrom the following detailed description'of a preferred embodiment of theinvention when taken in conjunction with the accompanying drawingswherein like reference numerals designate like elements throughout theseveral views.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of analarm device in accordance with the present invention illustrated asbeing operatively connected to a window to detect unauthorized movementthereof;

FIG. 2 is an enlarged front view of the alarm device of FIG. 1, thecover of the housing being removed to show the internal elements;

FIG. 3 is a longitudinal sectional view taken generally along the line33 of FIG. 2 but showing the cover of the housing in assembled position;

FIG. 4 is a transverse sectional view taken generally along the line 44of FIG. 3: and

FIG. 5 is a schematic circuit diagram of the control circuit utilized inthe alarm device of FIGS. 1-4.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to the drawings, andin particular to FIG. 1, an alarm device in accordance with the presentinvention is indicated generally at 10 and is shown in conjunction witha conventional double-hung window, indicated generally at 12. Forpurposes of illustration, the alarm device 10 is shown in FIG. 1 insubstantially greater size relative to the window 12 than the size ofthe actual production unit which is approximately three by five inches,considered in front elevation as in FIGS. 1 and 2. As will become moreapparent hereinbelow. the use of the alarm device 10 in conjunction withthe window assembly 12 exemplifies but one possible use of the alarmdevice. In general, the alarm device 10 may be employed to generate analarm system responsive to the unauthorized movement of an object towhich a control element is attached, or signal the movement of thecontrol element when positioned in a passageway or the like so as to beobstructed by movement of a person in the passageway.

The alarm device 10 includes a rectangularly shaped housing indicatedgenerally at 14, having a removable cover plate 16. Noting FIG. 3, thecover plate 16 is retained on the top of the rectangularly shapedhousing 14 by a retaining screw 18 the lower end of which is threadedlysecured in an upstanding boss 20 formed integral with or otherwisesuitably secured to the lower wall 22 of the housing 14. The housing 14is preferably made of a lightweight material such'as a suitablethermoplastic material. The cover plate 16 of the alarm device 10 has aplurality of openings 24 therethrough to facilitate the transmission ofan audible alarm signal from the alarm device as will be described morefully hereinbelow.

With reference to FIG. 2, taken in conjunction with FIGS. 3 and 4, thealarm device 10 includes alarm gen erating means, indicated generally at26, which, in the illustrated embodiment, comprises a Klaxon steadysignal electrically operated audible alarm 28 of known design. The alarm28 has a mounting bracket 30 secured to the lower surface thereof (FIG.3) which is suitably secured to and supported by an upstanding boss 32formed integral with the bottom 22 of the housing 14. A conductor strip34 has one end thereof interposed between the mounting bracket 30 andthe boss 32 and extends along the bottom 22 of the housing to anupturned end portion 36 which forms a contact for a conventional C sizealkaline DC battery cell, indicated in phantom at 38. The mountingbracket 30 of the alarm 28 serves as the negative or ground terminal forthe alarm control circuit to be described more fully below. While thealarm generating means 26 is described and illustrated herein as beingan audible tone generating means, it will be understood that the alarmmeans may comprise a visual signal device such as a light, or maycomprise means providing an output signal for a remote indicating means.

The battery 38 is connected in circuit with a second DC battery,indicated at phantom at 40, identical to the battery 38 to provide asource of electrical energy for the alarm generating means 26. To thisend, the positive terminal 42 of the battery 38 contacts an upstandingconductor strip 44 which is of a configuration to cooperate with theupstanding end 36 of the conductor strip 34 to resiliently receive thebattery 38 therebetween. Suitable battery support plates 46 are formedintegral with the housing 14 and serve to cradle the batteries 38 and inoperating position within the housing. The conductor strip 44 has anintegral conductive arm portion 48 adjacent the bottom 22 of the housing14 which normally resiliently contacts a second conducting arm 50 formedintegral with an upstanding conductive strip 52 which provides theground contact for the battery 40. The conductive strips or contacts 44and 52 are secured to the lower or bottom plate 22 of the housing means14 through suitable means such as rivets 54 and 56, respectively.

The housing 14 is preferably provided with a suitable opening 58 whichreceives an elongated end portion 60 of a circuit disabling key 62 madeof a non-conducting material such as plastic. The elongated end 60 ofthe disabling key 62 may be selectively inserted through the opening 58in the housing 14 and caused to separate the normally contactingconductive arms 48 and 50 and thereby open the series circuit betweenthe batteries 38 and 40 to open the circuit to the alarm generatingmeans 26.

The positive terminal 64 of the battery 40 contacts a conductive strip66 which is secured to a nonconducting support plate 68. The supportplate 58 is of planar rectangular configuration and is slidably receivedbetween and supported by inwardly directed projections 70 formedintegral with the housing 14 and having slots along their lengths toreceive the opposite edge portions of the support plate 68 as shown inFIG. 2 such that the support plate may be removed from the housing 14.

The support plate 68 supports switch means, indicated generally at 72,which is connected in circuit between the source of electrical energycomprising the batteries 38 and 40 and the alarm generating means 26 toeffect selective energizing of the alarm generating means. The switchmeans 72 includes a pair of fixed contacts 74 and 76 which compriseconductor strips formed integral with the conductive strip 66, the fixedcontacts 74 and 76 being formed to extend downwardly from the top edgeof the support plate 68 and upwardly from the bottom edge thereof,respectively, as illustrated in FIGS. 3 and 4. The switch means 72further includes a movable contact arm 78 which has a suitable openingmid-length thereof to allow the contact arm to be pivotally mounted on asupport pin 80 secured in normal relation to the support plate 68generally centrally thereto. The support pin 80 has a threaded endportion 82 which is received through a suitable opening in the supportplate 68 and has a nut 84 secured thereon to retain the support pin 80in fixed relation on the support plate 68. A compression spring 86 isdisposed about the support pin 80 between a reel 88 to be described morefully hereinbelow, and the movable contact arm 78 which engages anenlarged head portion 90 of the support pin 80. The opposite ends of thecontact arm 78 are formed to establish leg portions 92 and 94 which liein planes perpendicular to the plane of the main arm portion 78.

Noting FIG. 4, a tension spring 96 has its opposite ends connected,respectively, to the inwardly turned leg portion 92 of the movablecontact arm 78 and to a projection 98 formed integral with andprojecting outwardly from the support plate 68 adjacent the upper edgethereof. The tension spring 96 is adapted to urge the movable contactarm 78 in a counter-clockwise rotational direction, as considered inFIG. 4, to effect engagement of the end leg portion 94 with the fixedcontact 76. As will be described below, the contact arm 78 is alsorotatable in a clockwise direction to effect engagement of the legportion 94 with the other fixed contact 74.

The support pin 80 is made of a metallic conducting material so as to beconductively connected to the movable contact arm 78, which in turn ismade of a conductive metallic material. The support pin 80 isconductively connected to a conductor 100 adjacent the threaded end 82and nut 84, the conductor 100 having its opposite end connected to ametallic terminal 102 through a screw 104 received through a suitableopening in the bottom 22 of the housing 14 and having a nut 106 securedon the lower end thereof to retain the terminal 102 against a raisedboss formed on the bottom 22 of the housing. A conductor 108 connectsthe conductor 100 to a terminal 109 of the alarm 28 to complete acircuit from the alarm generating means 26 through the batteries 38 and40 and back to the alarm 28 through the conductor 108 when the movablecontact arm 78 is contacting either of the fixed contacts 74 or 76.

The alarm device 10 includes switch operating means for cooperation withthe movable contact arm 78 to selectively effect movement of the switcharm to engage the fixed contact 74 or allow movement of the switch armto engage the fixed contact 76 under the influence of the biasing spring96. Such switch operating means includes a control element 110comprising a trip wire or cord, preferably made of a monofilament nylonline, which acts directly on the movable contact arm 78 and is adaptedto be secured to an object under a predetermined tension to position thecontact arm intermediate the fixed contacts 74 and 76. To this end, thecontrol element 110 is wound upon the aforenoted reel 88 which is madeof a nonconductive thermoplastic material and is supported on thesupport pin 80 for rotational movement thereon-The reel 88 is urgedtoward the support plate 68 by the compression spring 86. The reel 88has a peripheral surfaceportion-which extends through a suitablerectangular opening 112 in the cover 16 of the housing 14 such that thereel 88 may be rotated on the support shaft 80 by one s thumb fromoutside the housing 14. The reel 88 is adapted to hold approximately 30feet of the control element line 110 and allows the control element lineto be played outwardly from the reel whereupon the control element lineis passed through an opening 114 in the leg portion 94 of the movablecontact arm 78 and through an opening 116 formed in the sidewall of thehousing 14. The opening 114 in the movable contact arm 78 and theopening 1 16 in the housing have smooth peripheral surfaces to allowfree sliding movement of the control element line 110. Theouter end ofthe control element 110 has a magnet 118 secured thereto formagnetically attaching the endof the control element to a metallic plate120 affixed to an L-shaped bracket 122 to the vertical leg portion ofwhich has a pressureadhesive surface 124 providing means to secure thebracket 122 to an object such as the horizontal window frame member 126of the window assembly 12 shown in FIG. 1. It will be understood thatthe outer end of the control element 110 may be secured to the windowframe member 126 or other object through any suitable means alternativeto the magnet 118 and bracket 122.

As noted, the control element 110 may be played-out from the reel 88 toallow the magnet 118 to be secured to the bracket 122 which is attachedto an object removed from the alarm device 10. To prevent free rotationof the reel, a flange portion 128 thereof has one or more V-shapedprojections or teeth 130 projecting outwardly therefrom toward theopposing surface of the support plate 68. The teeth 130 cooperate with aplurality of circularly disposed V-shaped teeth 132 formed integral withthe support plate 68 and lying on a circle having a radius equal to theradial distance of the teeth 130 from the axis of the flange 128 of thereel. In this manner, the compression spring 86 urges the reel 88 in adirection to position the teeth 130 intermediate the spaced teeth132thereby providing resistance to rotasupported within a suitablevopening in an end wall 136 of the housing 14. The thermostat means 134has a pair of terminals .138 and 140. The terminal 130 is connectedthrough conductors-142 and 144 to the conductive strip 66 so as to be incircuit with the batteries 38 and 40. The terminal 140 of the thermostatmeans 134 is connected through a conductor 146 to a positive terminal148 on the bottom of the alarm 28. The thermostat means 138 is of knowndesign and is responsive to a predetermined termperature rise to closethe circuit between the batteries 38 and 40 and the alarm 28 to energizethe alarm and effect an alarm signal when the temperature surroundingthe ala rm device reaches a danger condition such as would result from afire.

, FIG. 5 schematically illustrates the circuit for selectivelyelectrically connecting the alarm 28 of the alarm generating means 26 tothe energy source comprising the batteries 38 and 40, and shows thatwith the disabling key 62 removed to effect connection between theconductive arms 48 and 50, the alarm 28 may be energized through closingof the normally open thermostat switch means 134 or through engagementof the movable contact arm 78 with either of the fixed contacts 74 and76.

Having thus described a preferred embodiment of the present invention,its operation will now be briefly described. With the elements of thealarm device 10 assembled as hereinabove described, the housing 14 maybe secured to a wall or window frame adjacent a window, door orpassageway in which unauthorized movement it to be detected. In theapplication of the alarm device as illustrated in FIG. 1, the bracket122 would then be secured to the horizontal window frame member 126 andthe control element withdrawn or played-out from the reel to allow themagnet 110 to be magnetically attached to the metallic plate of thebracket 122. When mounting the alarm device 10 in an operating position,the disabling key 62 is inserted through the opening 58 to separate thecontact arms 48 and 50 and thereby open the circuit to the alarm 28through the batteries 38 and 40. After connecting the magnet 118 to thebracket 122, the reel 88 is moved by the operators thumb in a rotationaldirection to tighten the control element line 110 until the end leg 94of the movable contact arm 78 is positioned intermediate the fixedcontacts 74 and 76 as illustrated in FIG. 4. After roughly tensioningthe control element 110, the disabling key 62 is removed and the reel 88further rotated, if necessary, to assure placement of the contact arm 76intermediate the fixed contacts 74 and 76. The compression spring 86serves to maintain friction engagement of the teeth on the reel flange128 between the opposing teeth 132 on the support plate 68 such that thereel will remain in its set position with the control element 110 beingunder a corresponding predetermined tension to establish theintermediate position of the contact arm 78.

With the alarm device 10 so installed, if the lower window of the windowassembly 1 12 should be opened upwardly in an unauthorized manner, thetension in the control element 110 will be reduced to allow the biasingspring 96 to move the contact arm 78 into engagement with the fixedcontact 76 and thereby energize the alarm 28 giving an alarm signal.Alternatively, if the control element 110 and its associated magnet 118are secured to the lower window when in a desired raised position,unauthorized lowering of the window will increase the tension on thecontrol element 110 and cause the movable contact arm 76 to engage thefixed contact 74 and close the circuit to the alarm 28 to establish anoutput alarm signal. Similarly, if the alarm device 10 is placedadjacent a floor area close to a passage through which people pass, thecontrol element 110 may be placed across the passage area and secured ina predetermined tension to place the contact arm 78 intermediate thecontacts 74 and 76. Thereafter, should anyone effect an unauthorizedpassage through the passageway and contact the control element 110, itwould either place the control element in greater tension to effectmovement of the contact arm 78 with the contact 74 to establish an alarmsignal, or would pull the magnet 118 from the associated bracket 122' toslacken the control element sufficiently to allow move ment of thecontact arm 78 into engagement with the contact 76 to again close thecircuit to the alarm 28 and establish an alarm signal. Similarly, if thecontrol element 110 is cut, broken, or burned after having beeninstalled in the aforedescribed manner, an alarm will be established.

While a preferred embodiment of the present invention has beenillustrated and described, it will be understood that changes andmodifications may be made therein without departing from the inventionin its broader aspects.

We claim:

1. An alarm device for use in detecting movement of an object,comprising, in combination, housing means, electrically operated alarmgenerating means supported by said housing means, a source of electricalenergy supported by said housing means, circuit means selectivelyelectrically connecting said alarm generating means to said source ofelectrical energy, said circuit means including switch means having apair of spaced fixed contacts and a movable contact arm therebetween andbiasing means urging the movable contact arm to one and away from theother of said fixed contacts, said movable contact arm and fixedcontacts being connected in said circuit such that said circuit means isclosed when said contact arm is contacting either of said fixed contactsand open when said contact arm is disposed intermediate said fixedcontacts, a rotatable reel member, means including a length of cordwound about said rotatable reel memher, and releasable clutch means forresisting rotation of said reel member, said cord means acting directlyon said movable contact arm and having its free end adapted to besecured to the object, said clutch means being releasable to permitunwinding of said cord means from said reel member to facilitateattachment of said cord means to the object and to take up slack in saidcord means to place said cord means under tension of an amountsufficient to resist the force of the biasing means and hold saidcontact arm intermediate and out of engagement with said fixed contacts,whereby when said cord means is pulled, broken or otherwise disturbedsaid contact arm will be caused to contact one of said fixed contactsand to energize said alarm generating means.

2. An alarm device as defined in claim 1 wherein said movable contactarm has an opening therein, and wherein said cord means passes throughsaid opening and acts upon said contact arm to effect movement thereofwhen the tension in said cord is varied from said tension placedthereon.

3. An alarm device as defined in claim 1 wherein said reel member ismounted within said housing and includes a flange portion extendingoutwardly of said housing to allow said reel member to be rotatedthrough movement of said flange portion externally of said housing.

4. An alarm device as defined in claim 1 wherein said source ofelectrical energy comprises a pair of DC batteries normally connected inseries, said circuit means having a pair of separable contacts normallyconnecting said batteries in series, and including means adapted to beinserted between said last mentioned contacts to separate the same andopen said series connection between said batteries.

5. An alarm device as defined in claim 1 wherein said reel member ismounted within said housing for rotation about its longitudinal axis,and wherein said movable contact arm of said switch means is mounted forpivotal movement about the axis of rotation of said reel.

- 6. An alarm device comprising, in combination, housing means,electrically operated alarm generating means supported by said housingmeans, a source of electrical energy supported by said housing means,circuit means selectively electrically connecting said alarm generatingmeans to said electrical energy source, said circuit means includingswitch means comprising a pair of fixed contacts and a movable contactarm swingable therebetween, and biasing means urging the movable contactarm to one of said fixed contacts and away from the other, a rotatablereel having a length of cord wound thereabout and spring-biased,releasable clutch means for resisting rotation of said reel, said cordpassing through a provided opening in one end of said contact arm andhaving its free end adapted for attachment to an object, said clutchmeans being releasable to permit unwinding of the cord therefrom tofacilitate attachment of said cord to such object and to take up slackin the cord sufficiently to place the cord under tension and hold thecontact arm out of engagement with the fixed contacts and against theforce of the, biasing means whereby when the cord is pulled, broken orotherwise disturbed the contact arm will be caused to contact one of thefixed contacts and to energize the alarm generating means.

7. An alarm device as defined in claim 6 wherein said free end of thecord has a magnet attached thereto.

8. An alarm device as defined in claim 6 wherein the circuit meansincludes a pair of separable contacts aligned with an opening in thehousing through which a removable electrical insulating member isinsertable to separate the contacts and open the circuits to disable thealarm device.

9. An alarm device as defined in claim 6 wherein the reel and movablecontact arm are mounted to independently turn on a common axis locatedto one side of and spaced from the opening in the contact arm throughwhich the cord passes, said housing having a further opening thereinspaced from and to the opposite side of said opening in the contact armthrough which the cord is also threaded, said opening being so relatedthat the reel may be rotated on its axis to take up slack in the cordand thereby to center the contact arm spaced between the fixed contacts.

10. An alarm device as defined in claim 6 including thermostat meanssupported by said housing means and connected in circuit with saidcircuit means, said thermostat means being adapted to effect energizingof said alarm generating means when a predetermined temperaturesurrounding said thermostat means is reached.

11. An alarm device as defined in claim 10 wherein said thermostat meansis connected in parallel with the portion of said circuit having saidswitch means therein so that said alarm generating means may beenergized by said thermostat means while said swith means is open.

1. An alarm device for use in detecting movement of an object,comprising, in combination, housing means, electrically operated alarmgenerating means supported by said housing means, a source of electricalenergy supported by said housing means, circuit means selectivelyelectrically connecting said alarm generating means to said source ofelectrical energy, said circuit means including switch means having apair of spaced fixed contacts and a movable contact arm therebetween andbiasing means urging the movable contact arm to one and away from theother of said fixed contacts, said movable contact arm and fixedcontacts being connected in said circuit such that said circuit means isclosed when said contact arm is contacting either of said fixed contactsand open when said contact arm is disposed intermediate said fixedcontacts, a rotatable reel member, means including a length of cordwound about said rotatable reel member, and releasable clutch means forresisting rotation of said reel member, said cord means acting directlyon said movable contact arm and having its free end adapted to besecured to the object, said clutch means being releasable to permitunwinding of said cord means from said reel member to facilitateattachment of said cord means to the object and to take up slack in saidcord means to place said cord means under tension of an amountsufficient to resist the force of the biasing means and hold saidcontact arm intermediate and out of engagement with said fixed contacts,whereby when said cord means is pulled, broken or otherwise disturbedsaid contact arm will be caused to contact one of said fixed contactsand to energize said alarm gEnerating means.
 1. An alarm device for usein detecting movement of an object, comprising, in combination, housingmeans, electrically operated alarm generating means supported by saidhousing means, a source of electrical energy supported by said housingmeans, circuit means selectively electrically connecting said alarmgenerating means to said source of electrical energy, said circuit meansincluding switch means having a pair of spaced fixed contacts and amovable contact arm therebetween and biasing means urging the movablecontact arm to one and away from the other of said fixed contacts, saidmovable contact arm and fixed contacts being connected in said circuitsuch that said circuit means is closed when said contact arm iscontacting either of said fixed contacts and open when said contact armis disposed intermediate said fixed contacts, a rotatable reel member,means including a length of cord wound about said rotatable reel member,and releasable clutch means for resisting rotation of said reel member,said cord means acting directly on said movable contact arm and havingits free end adapted to be secured to the object, said clutch meansbeing releasable to permit unwinding of said cord means from said reelmember to facilitate attachment of said cord means to the object and totake up slack in said cord means to place said cord means under tensionof an amount sufficient to resist the force of the biasing means andhold said contact arm intermediate and out of engagement with said fixedcontacts, whereby when said cord means is pulled, broken or otherwisedisturbed said contact arm will be caused to contact one of said fixedcontacts and to energize said alarm gEnerating means.
 2. An alarm deviceas defined in claim 1 wherein said movable contact arm has an openingtherein, and wherein said cord means passes through said opening andacts upon said contact arm to effect movement thereof when the tensionin said cord is varied from said tension placed thereon.
 3. An alarmdevice as defined in claim 1 wherein said reel member is mounted withinsaid housing and includes a flange portion extending outwardly of saidhousing to allow said reel member to be rotated through movement of saidflange portion externally of said housing.
 4. An alarm device as definedin claim 1 wherein said source of electrical energy comprises a pair ofDC batteries normally connected in series, said circuit means having apair of separable contacts normally connecting said batteries in series,and including means adapted to be inserted between said last mentionedcontacts to separate the same and open said series connection betweensaid batteries.
 5. An alarm device as defined in claim 1 wherein saidreel member is mounted within said housing for rotation about itslongitudinal axis, and wherein said movable contact arm of said switchmeans is mounted for pivotal movement about the axis of rotation of saidreel.
 6. An alarm device comprising, in combination, housing means,electrically operated alarm generating means supported by said housingmeans, a source of electrical energy supported by said housing means,circuit means selectively electrically connecting said alarm generatingmeans to said electrical energy source, said circuit means includingswitch means comprising a pair of fixed contacts and a movable contactarm swingable therebetween, and biasing means urging the movable contactarm to one of said fixed contacts and away from the other, a rotatablereel having a length of cord wound thereabout and spring-biased,releasable clutch means for resisting rotation of said reel, said cordpassing through a provided opening in one end of said contact arm andhaving its free end adapted for attachment to an object, said clutchmeans being releasable to permit unwinding of the cord therefrom tofacilitate attachment of said cord to such object and to take up slackin the cord sufficiently to place the cord under tension and hold thecontact arm out of engagement with the fixed contacts and against theforce of the biasing means whereby when the cord is pulled, broken orotherwise disturbed the contact arm will be caused to contact one of thefixed contacts and to energize the alarm generating means.
 7. An alarmdevice as defined in claim 6 wherein said free end of the cord has amagnet attached thereto.
 8. An alarm device as defined in claim 6wherein the circuit means includes a pair of separable contacts alignedwith an opening in the housing through which a removable electricalinsulating member is insertable to separate the contacts and open thecircuits to disable the alarm device.
 9. An alarm device as defined inclaim 6 wherein the reel and movable contact arm are mounted toindependently turn on a common axis located to one side of and spacedfrom the opening in the contact arm through which the cord passes, saidhousing having a further opening therein spaced from and to the oppositeside of said opening in the contact arm through which the cord is alsothreaded, said opening being so related that the reel may be rotated onits axis to take up slack in the cord and thereby to center the contactarm spaced between the fixed contacts.
 10. An alarm device as defined inclaim 6 including thermostat means supported by said housing means andconnected in circuit with said circuit means, said thermostat meansbeing adapted to effect energizing of said alarm generating means when apredetermined temperature surrounding said thermostat means is reached.